Live-air-actuated sleeve valve for tools



Oct. 5

L. W. GREVE LIVE AIR ACTUATEDSLEEVE VALVE FOR TOOLS 2 Sheets-Sheet 1 Filed Feb. 15. 1923 Oct. 5 I

- L. w. GREVE LIVE AIR ACTUATEDSLEEVE VALVE FOR TOOLS Filed Feb. 15, .192: 2 Sheets-Sheet 2 ATTORNEYfS.

Patented (let 5, 1926,

r scan a t ca a LOUIS V. GEEVE, CLEVELAZED, OHIO, ASSIG'LIOR OF GEE-HALF TO THE CLEVELAND PNEUIEATIG TOOL COILE'EMT'SZ' All?) ONE I-EALF T0 vTHE CLEVELAND ROCK DRILL GOIIIPANY, BOTH OF CLEVELAND, OHIO, AND BOTH CORPORATIONS OF OHIO.

LlVE-AIB-ACTUATED snunvn ALVE non TooLs'.

Application filed February 1923. Serial No. 619,142.

My invention relates to a novel construetion of a live air actuated, sleeve valve adapted for use in apneuinatic hammer, rock drill or similar hammering implement and comprises a novel construction of a valve block, valve cap, valve and co-acting cylinder and piston, whereby a very compactand e'liicient structure is produced, the valve being actuated in both its forward and rearward directions by direct live air pressure. whereby a positive and accurate movement is imparted to the valve and the latter is held against its seat in its extreme positions without fluttering, for the proper period prior to shifting. 7

it further consists of a novel construction of a live air actuated, hollow sleeve valve adapted to have its piston pass through it during its rearward stroke, and a novel construction of co-actingf ports and passages common to said valve and the co-acting piston, whereby the reciprocations thereof are controlled.

It further consists of a novel construction of a hollow valve, a coaeting piston and their adjuncts for effecting the admission and exhaust of the motive fluid at the proper periods.

It further consists of a novel construction of a hollow, live air actuated, sleeve valve, through which the piston passes on its rear stroke, said valve being shifted in bothdirections by direct live air pressure, in con tradistinction to tools, wherein the valve is shifted in one direction by air compressed between the piston and valve. v 7

It further consists of a novel construction of constantly open live air passage, communicating with a pick o'lf port, and having a port leading to a live air pocket, constantly supplied with live air adapted, in conjunction with live air acting on the forward face of the valve, to shift the valve rearwardly, when the piston, in making its forward or down stroke, moves forwardly out of the valve.

It further consists in conjunction with my novellive air actuated sleeve valve and its" adjuncts, of novel means controlled by the tachecl position.

piston for exhausting the forward end of the piston chamber. I

lit'further consists of other novel features of construction and advantage, all as will be hereinafter fully set forth. I

F or the purpose of illustrating my invention, I have shown in the accompanying drawings forms thereof which are at present preferred by me, since they will give in prac: tice satisfactory and reliable results, although it is to be understood that the vari ous instruinentalities of which my invention consists can be variously arranged and organized and that my invention is not limited to the precise arrangement and organization of these instrumentalities as herein shown and described. v

Figure 1 represents a longitudinal sectional view of alive airaotuated sleeve valve and its adjuncts and a pneumatic hammering implement to which the same is applicable, the piston being shown as about to begin its return stroke and the valve being seated in its extreme rear position; V Figure 2 represents a section on the line 22' of Fig. 1 showing the constantly open live air admission port, the kick-0E port and the port which leads constant live air-pres: sure to the live air'pocket or shoulder ofthe', valve, whereby the same is shifted rear.- wardly.

Figurei3 represents on an enlarged scale a sectional view similar to Fig. l-butshowing the piston and valve in a position opposite to that shown in Fig. 1,,the piston bea ing in its extreme rear position, and the valve having shifted to its extreme forward posi tion. i

Figure 4 on line Fig; 1. I

Figure 5 represents a perspective viewv of the live air actuated, sleeve valve in de- 1 Similar numerals of reference indicate corresponding parts;

Referring to the drawings: l Vhile my invention init's broad aspects, so far as concerns the hollow, live'air actuated valve, its piston and the. co-acting ports represents a transverse section While the piston 4 is' moving rearwa and passages, is cap-able of adaptation to any portable pneumatic hammering imple ment, as a riveter, chipping hammer, rammer, rock drill or the like, I have shown it embodied in the present instance in a portable hand held rock drill, in which the forward end of the piston serves automatically to rotate the drill steel through the medium of a rifle nut and rifle flutes on the piston itself. I have confined the following description principally to the novel con struction and mode of operation of the live air actuated, sleeve valve, its piston and the co-acting ports and passages, whereby the reciprocations of the valve and piston are effected, since the details of the assembly, and the construction of the forward portion of the implement, the drill holder, the water supplying devices, and the like, form no part of my present invention and can be variously arranged and organized, as will be evident to those skilled in the art.

1 designates my novel construction of hammer, the same comprising the cylinder 2, having the piston chamber 3, in which reciprocates the piston 4, having the forward extension 5 of reduced diameter and the rear cavity 6, indicated in dotted lines, which is of greater diameter than the forward extension 7 of the valve cap 8, which is pro vided with the valve block 9, containing ports and passages which co-act with the valve 10, seen detached in Fig. 5, the parts being held in assembled position by the outer head- 11 and the bolts 12. The valve and piston are arranged in longitudinal alignment and the piston at its extreme rearward stroke is positioned within the valve as seen in Fig. 3, and the various parts are so designed and correlated that a very compact and efficient structure is produced. in lig. 1, I have shown the position of the parts at the beginning of tie rearward stroke of the pistond, the valve 10 being at this period in its rearmost position and the piston being shown as starting on its rearward stroke. Live air is admitted to the pocket 13.. by any suitable means, and passes through the screen 14, through the series of holes 15 into the annular groove 16 annular valve groove 17, into series of small holes 18, passage 19 and port 20 to the front shoulder 21. of the piston 4t, whereupon the latter is impelled rearwardly from the position seen in Fig. 1 to the position seen in 3. dly, the exhaust is leaving the rearend of the piston chamber 3 through the ports 22, 23, 24 and main exhaust opening 25 the piston 4 starts rear'vvardly, from the position seen in Fig. 1 and during its initial rear-.

ward movement, the kickoff port 26, is covered, There is constant live air pressure in the passages 27 and 28 (see Fig. 2), the passage 27' communicating with'the-air supplying pocket 13, and there will consequently be an accumulation of live air built up in the chamber 29 (see Figs. 1 and through the port 30, whereby the valve 10 will be pressed r-earv-iardly a ainst its seat seen in Figs. 1 and 2, during the initial rearward movement of the piston during which period the forward end or valve face 31 is open or exposed to exhaust pressure only. l l hile he valve and have some live air )ressure on them due to leakage from the .;rooves 1.6 1.7, live air press neon the s iouleer or valve fat-e obviously preponderates, since it does not depend un'on leak e, but upon the direct const l .e air s1 ly introduced through the port tivelv held in its rearware position, as seen in Fig. 1. against its seat for the proper period without fluttering. its the hammer or piston moves rearwardly from the position seen in Fig. 1 to the position seen in Fig. 3., it closes exhaust ports rd (see and the live air lealn-ige around the rear valve face 33, will build 15 pressure on the rear race of aid and said rear valve l v hile some cushioning action or compression which is always present, when a pr on of any engine reaches either of its extic c po.- sitions during each stroke, this is of minor value in my construction, con

positc valve faces 0 the valve moves forw" dly or trip to the po ion seen in J 1r should be made not to .ncover or were omitted entirely, it is ap t that the piston it would finally uncover the hrs--- haust port 36, as it its extreme rear position seen in 3. and ct the res lls above *aolained. The parts are nowin 0 n l e I n the position seen in the piston being in its rearward position and within the valve 10 and about to begin its strikir; or forward stroke, at which period the va .e ll) is in its extreme forward position.

Live now freely flows from groove 16, across the rear valve face 33, to the rear of thepiston chamber 3, and forces the pie ton 4L- forwardly. At this time the front L 1 s 27 and 28, and the valve is thus posipiston chamber is exhausting through the flutes '35 and 37, exhaust ports 36 and 25, and through passages 19 and 38, around the valve groove 17, groove 39 passages 24 and 25 to the atmosphere. The valve is now held in its forward position by the live air pressure on the rear face 33. As the piston continues on its down or f ard stro the kick-off port 26 will be covered, live air pressure will build up in the port 30,-and the live air pocket 29, causnp; pressure on the face 3% of the valve thus tending to balance the pressure on the opposite face W11 *1 the piston uncovers the forward valve ce the live air pressure in the rear of the piston chamber 8 will bec me effective on this '31, and the sum of the pressures on the faces 31 and 34 will then'overcoine the pressu on the face 83 and the valve will be'forced or shift rearWa-rdly from the positions see; in Fig. 3 to the position seen in 1 thus completing the cycle.

40 designates a direct live air port, seen in Fig. 3, which may be used as an alternative if desired to lead live air directly to the rear valve face 33, to make the valve shift or trip quicker on the rear stroke of the hannner.

It Will be apparent from the foregoing that my novel valve is 'in'iper ate and is not weakened by the presence nolcs or ports therein and consequently it can readily and cheaply manufact' be very durable in practical use.

It will further be apparent that my novel arrangement of ports and passages, and by the provision of the chamber 6 in the piston, the piston is 'hollowedout for a great portion of its length thus reducing its weight and by causing; the piston in its rcarmost stroke to enter the valve, as seen in Fig. 3, an en emely short and compact implement is produced, Wherein the length overall and he weight will be reduced to a minimum. it will, of course, be understood while in all tools of this character, a cushion is former to a greater or less extent at each end of the piston chamber 8, so that the piston will not impact upon the end wallsof the piston chamber, that my novel alve is not depend out upon, or actuated in either direction by, this cushion or compression of the air, but is actuated or shifted in both directions solely by live air pressure, the valve being It will further be evident that by his construction and arrangement of ports-andpassag'es, a very accurate and instantaneous tripping or shifting of the valve into both its extreme positions iselfected, and While I have found in practice that my novel hammer will operate effectively with or without the live air port 40 seen in Fig. 3, it will operate somewhat more effectively when the said port s0 is employed.

It will be evident that in the manufacture and assembling of my novel valve'niechanisi'n and its adjuncts, theparts may be constructed and assembled somewhat difiercntly fron the shown, but I have found the construc-- tion shown to operateex lently in practice under all conditions. l lhile I have shown my novel valve mechanism in the present instance, as embodied in relatively short stroke tool, it will be apparent that by-the proper lengthening or modification of the ecessary ports and passages, my novel valve mechanism can beemployed with equal facility in long stroke pneumatic tools, such as riveters, where the hammering piston is usually a plain cylindrical bolt and has a length of stroke considerably in excess of its own length. i

Having thus described my invention What I clai new and desireto secure by Letr of the character stated, a 1 piston chamber therein, a piston diameter and provided with flutes serv ward stroke, front and rear shoulders on said valve, an annular'outcr groove in said valve at the rear of said'rear valve shoulder serving alternately as a live air inlet and an era haust groove, and a head at the rear of'said groove controlling the inlet to the frontof s piston chamber, means for admitting Iss1 L live air to said front and rear shoulders to shift said valve by live air, and a cap for said valve box having a forwa d projection serving as a guide for the inner bore of said valve. l p x i f 2. In a device ofthe character stated, a cylinder, a piston chamber therein, a pi ton hollowed out in its rear, a v2 ve box, a cap therefor having a forward projection of less diameter: than the cavity in said piston,'a-n imperforate sleeve valve therein positioned around said forward extension and provider with front and rear shoulders said cap having a forward extension serving as a guide for the inner bore of said valve, an outer groove in the rear-of said rear shoulder serving alternately as a live air inlet and an exhaust groove,and a rear head controlling the inlet to the front of said piston chamber,

means for admitting live air to said front and rear shoulders of said valve to shift the latter in opposite directions by live air only, and exhaust passages atthe opposite ends of said piston chamber.

- her having a forward extension 3. In a device of the character stated, a cylinder, a piston chamber therein, a piston in said chamber having its forward end prolonged, of reduced diameter and provided with exhausting flutes on said forward end, and its rear end hollow, a valve box, a cap therefor having a hollow forward extension through which the piston moves in its rearward movement, said cap having also a larger forward extension serving as a guide for the inner bore of said valve, a hollow sleeve valve therein in line with. said piston, the latter passing through said valve on its rearward stroke, front and rear pressure shoulders on said valve, a groove in the rear of said shoulders serving alternately as a live air inlet and an exhaust groove, and a heat at the rear of said rear groove controlli g the inlet to the front of said piston chain exhaust devices for the rear of said piston chamber, and means for admitting live air to said front and rear faces of said valve t shift it by live air. 7 '4. In a device of the character stated, a cylinder, a piston chamber havi a reduced forward extension provided with exhanst flutes therein, a hollow piston in said chamber, a valve box, a cap for the latter havi a hollow forward extension ada ted to entor the piston on the rearward movement of the latter, said cap also havi e a l a rorward extension adapted to enter tl bore of said valve when the la ter is in its rearmost position, a hollow imperforate sleeve valve in said b 3, said piston passing through said valve on its rearward stroke, front and rear shoulders on said valve, an annular outer groove at the rear of said rear shoulder serving alternately as a live air inlet and an exhaust groove, and a head at the rear of said groove controlling the inlet to the front end of said piston chamber, an exhaust passage at the front of the on chamberuncontrolled by said valve, another exhaust'passage at the front of said chanber controlled by said valve, exhaust passages at the rear of said piston chamber con trolled by both the piston and valve, kickoff port alternately opened and closed by said piston, and live air passages leading to said front and rear valve shoulders, the live air passage leading to said frontvalve shoulder communicating with said kick-off port.

5. In adevice of the character stated, a cylinder, a hollowpiston chamber having a reduced forward extension provided with xhaust flutes therein, a piston in said chamber, a valve-box, a hollow imperforate sleeve valve therein, said piston passing through said valve on its rearward stroke, front and rear shoulders on saidvalve, an annular outer groove at the rear of saio rear shoulder serving alternately as alive air inlet, and

an exhaust groove and a head at the rear of said groove controlling the inlet to the front of said piston chamber, a cap for said valve box having a hollow rearward extension serving as a guide for the inner bore of said valve when the latter is in its rearmost position, and means for admitting live air to said front and rear shoulders to shift said valve by live air only, the live air passage to the front of said valve having a communication with a kick-off port alternately opened and closed by said piston.

6. in a device of the character stated, a cylinder, a piston chamber therein, a piston in said chamber having its forward end prolonged and of reduced diameter and provided with exhausting flutes, and its rear end hollow, a valve box, a cap therefor having a hollow forward extension which closes said piston when the latter makes its rearward stroke, said cap also having a larger forward extension serving as a guide for the inner bore of said valve when the latter is in its extreme position, a hollow sleeve valve in line with said piston, the latter passing through said valve on its rearward stroke, a cap for said valve box having a forward projection of less diameter than the cavity piston, said valve surrounding said project front and rear pressure faces on said valve, a groove in the rear of said shoulder se ving alternately as a live air inlet and an exhaust groove, and a head at the rear of said 'roove controlling the inlet to the front of said piston chamber, exhaust de vices for the rear of said piston chamber, a kick off port alternately opened and closed by said piston and means for admitting live air to said front and rear faces of said valve to shift it by live air, the live air passage to the front valve shoulder communicating with said kickoff port.

'Z. in device of the character stated, avalve comprising a cylindrical body portion having a passage of uniformdiameter therethrough, front and rear pressure faces thereon, a groove in the rear of said rear face serving to control live air inlet and exhaust and a rear head serving to control the inlet to the forward end of the piston chamber, in combination with a piston adapted to enter said valve on its return stroke, a piston chamber for saidpiston, inlet and exhaust passages in said piston chamber controlled by said valve, live air inlet passages leading to said front and rear pressure faces, a kick off port alternately opened'and closed by i said kick off.

LOUIS N. GREVE. 

